While designing buildings that create more energy than they take in is sound environmental policy, it can also be a good way to draw customers to your business, as one Florida credit union discovered. "A few years ago in central Florida, John Santarpia had an idea. He was the president and C.E.O. of a credit union and felt he needed to do something to improve its image. 'We're a medium-sized credit union and there's a lot of competition,' Santarpia said. 'We wanted to stand out.' He and his colleagues had found a lot in Lakeland, a city of about 100,000 residents, with an ice cream shop on it."